The invention relates to a flexible foldable solar generator for space vehicles.
The invention relates to a flexible foldable solar generator for space vehicles according to the precharacterising portion of claim 1.
Such solar generators are designed as large and light carrier structures which preferably only contain flexible foil substrates, folded bellows-like, and which are opened out in orbit by telescope-like mechanisms so as to cover a large area.
To take up little room in the hold, these foil surfaces have to be folded at very small spacing of only approx. 2 mm. To this effect, the individual large-area modular carrier foil sections of the solar generator comprise an electrical current-conducting track system which is suitable for interconnecting individual sections in a simple and space-qualified way. The electrical current-conducting track system must generally meet the exacting requirements for operation in space, such as the high thermal alternating stress resulting from sun and earth shadow, as well as extreme demands for reliability throughout the entire duration of the mission. Furthermore, the electrical connecting elements must be designed such that they remain free of any tension load. In addition, for the purpose of exchange and repair of entire solar generator sections, repeated non-destructive disconnection and reconnection must be possible.
From DE 3210312 C3 a solar generator for space vehicles is known which is composed from individual carrier foil sections. The individual sections are connected by means of piano-type hinges. Polyimide foil with one-sided copper lamination, if necessary also with double-sided copper lamination, is used as the starting material for carrier foils.
The reverse side of the solar generator comprises an electrical current-conducting track system made using the photoresist etching process. Starting from the outer carrier foil section, the individual current-conducting tracks for the electrical current obtained from solar cells, is conducted as far as possible on the inside along the entire length of the solar generator, to connectors at the satellite. After infeed to the middle, the current-conducting tracks of the next carrier foil section extend from the middle, in close proximity to the current-conducting tracks of the outer carrier foil sections etc. so that overall on the reverse side, a pine-tree like configuration, with increased occupation of the reverse side towards the inside, of etched conducting tracks results. All current-conducting tracks commence at positive or negative connection positions of the solar cell modules. They are led across fold lines by means of fold-conducting tracks, and across joint axes at the section ends by means of section-conducting track transitions. Such a current-conducting track requires considerable expenditure in material and production effort and significantly increases the weight of the solar generator, thus causing increased launching costs of the space vehicle.
It is an object of the invention to provide a cost-effective, flexible, foldable solar generator for use on space vehicles.
It is thus the object of the invention to create a cost-effective, flexible, foldable solar generator for use on space vehicles.
It is of advantage if the invention uses a particular way of connecting the solar cell which makes it possible to completely do without current-conducting tracks within the array surface.
Apart from cost savings during production and savings in material, there is a particular advantage in reduced weight as a result of being able to do without the current-conducting track system in the array surface and being able to do without through-hole plating which tends to cause operational breakdowns.